Test Prep Test Prep Certifications OAT Questions & Answers

• Question 201:

  Juliet is on the physics portion of her OAT. It has 40 questions to be done in 50 minutes. She has completed 20 questions in 30 minutes. How much time does she have for each remaining question?

  A. 30 seconds

  B. 45 seconds

  C. 60 seconds

  D. 90 seconds

  E. 100 seconds

  Correct Answer: C

  Juliet has 20 questions remaining (40 total questions - 20 questions answered) with 20 minutes remaining (50 total minutes - 30 minutes used). Thus, she has 1 minute per question remaining.

• Question 202:

  In a classroom of 189 students, the ratio of boys to girls is 5 : 4. How many boys are there in the classroom?

  A. 38

  B. 84

  C. 105

  D. 120

  E. 155

  Correct Answer: C

  The simplest way to approach these problems is to divide the total number of students (189) by the

  combined ‘parts’ (5 + 4 = 9). Thus 189 ÷ 9 = 21.

  Multiply 21 by the gender of interest ratio (5): 21 × 5 = 105 male students.

  For females you would multiply 21 by 4 = 84 female students.

  Add 105 + 84 to verify = 189.

• Question 203:

  A circle is stretched out and its circumference is increased by 10%. What is the percent increase of the area of that circle?

  A. 10%

  B. 16%

  C. 21%

  D. 25%

  E. 30%

  Correct Answer: C

  The circumference of a circle can be expressed with the following formula: C = 2πr

  Notice how this means the radius is proportional to the circumference. This means that a percentage increase in the circumference will have the same percentage increase in the radius. Thus, if the circumference increases by 10%, so does the radius. Insert a random value for the radius. For this example, 10 will be used. If we were to increase the circumference by 10%, the radius (10) must also be increased by 10%. 10% of 10 is 1, thus an additional 10% of 10 will be 11.

  The area of a circle can be expressed with the following formula: A = π(r2). If we insert our original radius value of 10, our area will be: π(102)= 100 π.

  The area of our modified and expanded circle will be: π(112)= 121 π.

  To find the percentage increase: [(121 π – 100 π) / (100 π)] × 100 = 21%

• Question 204:

  5 friends just got hired for a job. 4 of them will earn $12 an hour, and the fifth person will earn $3 more than the average of all five salaries. How much does the fifth person make?

  A. $13

  B. $13.75

  C. $14.25

  D. $15 E. $15.75

  Correct Answer: E

  Solve this algebraically. Solve for x (amount fifth person gets paid). x = [((4 × 12) + x) / 5] + 3 5x = 48 + x + 15 5x = 63 + x 4x = 63 x = 15.75

  The 5th friend makes $15.75. This can be confirmed by adding up all 5 people's pay and finding the average: (12 + 12 + 12 + 12 + 15.75) / 5 = 12.75.

  $15.75 is $3 higher than the average of $12.75

• Question 205:

  What is the average of: 15, 25%, 1/2 and sin0?

  A. 3.02

  B. 3.94

  C. 4.20

  D. 4.64

  E. 5.21

  Correct Answer: B

  The important part is to do these as quick as possible to leave room for the lengthier QR problems. Simply convert the numbers to 15, 0.25, 0.5 and 0. Add them up and divide by 4 to find the average.

• Question 206:

  A square has a perimeter of x and an area of 2x. What is x?

  A. 8

  B. 16

  C. 20

  D. 24

  E. 32

  Correct Answer: E

  If a square has a perimeter of 32 (x), then its sides must be 8. The area is then: 8 × 8 = 64, or 2x.

• Question 207:

  Which statement correctly describes the elastic limit of a metal rod?

  A. The elastic limit occurs when a deformed object will no longer return to its original shape.

  B. The elastic limit occurs when the rod breaks.

  C. The elastic limit occurs when the stress stops producing a strain.

  D. The elastic limit assumes that the forces between molecules in a metal act like springs.

  Correct Answer: A

  When an external force deforms a solid material, it will return to its initial position when the force is removed. This is called elasticity and is exhibited by springs. If too much force is applied and the elastic limit is exceeded, the rod won't return to its original shape any longer. As with springs, the deformation is directly proportional to the stress. The elastic limit occurs in rods subjected to a tensile force when the strain stops being directly proportional to the stress. The typical pattern when the force increases is that the strain increases linearly, then it doesn't increase as much, and then it breaks.

• Question 208:

  Two cars driving in opposite directions collide. If you ignore friction and any other outside interactions, which of the following statements is always true?

  A. The total momentum is conserved.

  B. The sum of the potential and kinetic energy is conserved.

  C. The total velocity of the cars is conserved.

  D. The total impulse is conserved.

  Correct Answer: A

  In a closed system (when you ignore outside interactions), the total momentum is constant and conserved. The total energy would also be conserved, although not the sum of the potential and kinetic energy. Some of the energy from the collision would be turned into thermal energy (heat) for example. Nor is the total velocity conserved, even though the velocity is a component of the momentum, since the momentum also depends on the mass of the cars. The impulse is a force over time that causes the momentum of a body to change. It doesn't make sense to think of impulse as conserved, since it's not necessarily constant throughout a collision.

• Question 209:

  A person walks 4 meters in a single direction. He or she then changes directions and walks an additional 9 meters. What is the total magnitude of the displacement of the person?

  A. It is 13 meters.

  B. It is always larger than 9 meters but less than 13 meters.

  C. It is less than 13 meters and as small as 5 meters.

  D. It is less than 5 meters.

  Correct Answer: C

  Displacement is a vector that indicates the change in the location of an object. Answer 1 would be correct if the question asked for the total distance the person walked or if the person didn't change direction. If the person turned around 180? the displacement could be as small as 5 meters. If the person changed directions only a fraction of a degree, its magnitude would be less than 13 meters, not as large as 13 meters.

• Question 210:

  A lead sphere 10 centimeters in diameter is attached to a 10-meter wire and suspended from a beam in a large warehouse. A lead sphere 1 meter in diameter is hung next to the smaller sphere, almost touching. Ignoring friction, which statement is true?

  A. The small sphere will move slightly towards the big sphere, but the big sphere will not move.

  B. The big sphere will move slightly toward the small sphere, but the small sphere will not move.

  C. Neither sphere will move.

  D. Both spheres will move slightly towards each other.

  Correct Answer: D

  There will be a gravitational force of attraction between the two spheres determined by the universal constant of gravity, the distance between the spheres, and the mass of the spheres. Since both objects are affected by this force (remember, Newton's 3rd law says the force needs to be equal and opposite), both objects will experience a slight acceleration and start moving towards each other a tiny amount (when we ignore friction). Using F = ma, you know that the less massive sphere will experience a larger acceleration than the more massive one.